A recent study conducted by researchers at Cambridge University showed that chronic diseases can get triggered by the activation of certain genes on a seasonal basis.

Researchers associated with the study told that serious medical conditions like heart disease and rheumatoid arthritis, can found to be more common in winters.

The Cambridge University researchers for the study examined the DNA of 16,000 people in an effort to understand how actually the human immune system changes over the course of year.

Researchers examined nearly 23,000 genes, and found that around 25 % of human genes are more active at some times of year than others. They further told that many of these genes are related to inflammation and the immune system, which could explain the rise in illness during wintertime.

Previously medical researchers have known that certain diseases including, Type 1 diabetes and multiple sclerosis, affect patients more at some times of year than others.

But this study was the first of its kind to show that these changes could be due to seasonal changes taking place within immune systems.

John Todd, director of the JDRF/Wellcome Trust Diabetes and Inflammation Laboratory said, “In some ways, it's obvious but no one had appreciated the extent to which this actually occurred. The implications for how we treat disease like Type 1 diabetes, and even how we plan our research studies, could be profound”.

Furthermore, researchers even examined blood and fat samples from across the world and compared the samples taken at various times of the year.

Gene cycles were found to have variations at opposite times of years in subjects from the Northern and Southern Hemispheres. For example, People in Iceland, which sees months of sunlight and darkness, were found to have yet a different pattern.

Investigators believe this new study could point the way to medical treatments tailored to the current season, providing another way of customizing health care.